I have a client in IL getting ready to break ground in a month or so...

I have a client in IL getting ready to break ground in a month or so to build a barndominium and is planning on doing the build almost entirely himself. I have carriers that will write the structure but not the builders risk if the named insured is doing the build. American Modern said they'll write but won't add builders risk until four walls and roof are on. Who will write this risk and how do I approach piecing this together?